Methods, systems, and apparatus for detecting arc flash events using light and time discrimination

Abstract

A power equipment protection system includes a circuit breaker, a current sensor configured to measure a current through a circuit, a light sensor configured to detect a light event, and a controller communicatively coupled to the current sensor and to the light sensor, wherein the controller is configured to determine whether the light event originated from operation of the circuit breaker.

What is claimed is: 
     
       1. A method of operating a circuit breaker, said method comprising:
 detecting a light event using a light sensor; and 
 determining, by a controller, whether the light event originated from operation of the circuit breaker. 
 
     
     
       2. A method in accordance with  claim 1 , further comprising measuring a current level through a circuit using a current sensor. 
     
     
       3. A method in accordance with  claim 2 , further comprising determining whether the light event is detected within a time period during which the circuit breaker is configured to open in response to the current level. 
     
     
       4. A method in accordance with  claim 3 , further comprising activating an arc flash containment device when the light event is detected outside of the time period. 
     
     
       5. A method in accordance with  claim 1 , further comprising receiving a signal from the circuit breaker indicating that the circuit breaker is opening. 
     
     
       6. A method in accordance with  claim 5 , further comprising ignoring the light event during a time period associated with the circuit breaker opening. 
     
     
       7. A method in accordance with  claim 1 , further comprising detecting a decrease in the current level indicative of the circuit breaker opening and ignoring the light event during a time period associated with the circuit breaker opening. 
     
     
       8. A power equipment protection system comprising:
 a circuit breaker; 
 a current sensor configured to measure a current through a circuit; 
 a light sensor configured to detect a light event; and 
 a controller communicatively coupled to said current sensor and to said light sensor, said controller configured to determine whether the light event originated from operation of said circuit breaker. 
 
     
     
       9. A power equipment protection system in accordance with  claim 8 , wherein said controller is further configured to determine whether the light event is detected within a time period during which said circuit breaker is configured to open in response to the current level. 
     
     
       10. A power equipment protection system in accordance with  claim 9 , wherein said controller is further configured to determine the time period based on the current level. 
     
     
       11. A power equipment protection system in accordance with  claim 9 , wherein said controller is further configured to activate a circuit protection device when the light event is detected outside of the time period. 
     
     
       12. A power equipment protection system in accordance with  claim 8 , wherein said controller is further configured to receive a signal from said circuit breaker indicating that said circuit breaker is opening. 
     
     
       13. A power equipment protection system in accordance with  claim 12 , wherein said controller is further configured to ignore the light event during a time period associated with said circuit breaker opening. 
     
     
       14. A power equipment protection system in accordance with  claim 8 , wherein said controller is further configured to detect a decrease in the current level indicative of said circuit breaker opening and to ignore the light event during a time period associated with said circuit breaker opening. 
     
     
       15. A controller for use with a power equipment protection system, said controller comprising:
 a processor configured to:
 receive a signal representative of a measured current level from a current sensor; 
 receive a signal representative of a detection of a light event from a light sensor; and 
 determine whether the light event originated from operation of a circuit breaker. 
 
 
     
     
       16. A controller in accordance with  claim 15 , further comprising a memory area configured to store circuit breaker trip data, including a plurality of current levels and a respective time period necessary for a circuit breaker to open at each of the plurality of current levels. 
     
     
       17. A controller in accordance with  claim 16 , wherein said processor is further configured to determine whether the light event is detected within a time period during which the circuit breaker is configured to open in response to the current level. 
     
     
       18. A controller in accordance with  claim 17 , wherein said processor is further configured to activate a circuit protection device when the light event is detected outside of the time period. 
     
     
       19. A controller in accordance with  claim 15 , wherein said processor is further configured to receive a signal from the circuit breaker indicative of the circuit breaker opening and to ignore the light event during a time period associated with the circuit breaker opening. 
     
     
       20. A controller in accordance with  claim 15 , wherein said processor is further configured to detect a decrease in the current level indicative of the circuit breaker opening and to ignore the light event during a time period associated with the circuit breaker opening.